1. Field of Invention
The present invention relates generally printed products, and more particularly to a feeder device for positioning the printed products along a conveying path.
2. Description of the Related Art
In the printing industry, a feeder is conventionally used to pull off and convey printed products from a stack into a collector, where the printed products may be processed in various ways. For example, a feeder can be used to supply cards or merchandise samples to be glued on printed products. The feeder can also be used to supply and insert ads into newspapers and magazines. In all cases, these feeders must meet high quality standards with respect to capacity and operational safety. Also, since feeders are generally manufactured in large quantities, an easy and cost-effective large-scale production of these feeders should also be possible.
A conventional feeder of the above-described type is disclosed in Swiss Patent Application 493 337 A, wherein a gripping element is used to pull signatures from a stack and an expanding element is used to open the signatures. The signatures are then dropped onto a sword and later conveyed from the sword onto a conveying chain. The gripping element and the expanding element are arranged on shafts, which are positioned on two side plates that are joined by crosspieces.
Another conventional feeder used for supplying printed products to a conveying channel is disclosed in European Patent Application 1 231 176 B. In this feeder, a shaft is positioned on two end plates on the sides of a frame and is used for pulling printed products from a stack. The shaft includes grip disks that are fixedly mounted thereon, so as to rotate along with the shaft. The grip disks are provided with grippers, which pull respectively one printed product from the stack.
The conventional feeders described above are typically expensive to assembled and manufacture. What is needed is a feeder that can be produced and assembled at lower expense than the conventional feeders.